1. Field of the Invention
The present invention belongs to the field of the art synthesizing optically active amino acids. Specifically, the present invention relates to a process for conducting enantioselective hydrolysis by utilizing catalytic antibodies. More specifically, the invention relates to processes for enantioselectively hydrolyzing amino acid ester derivatives with catalytic antibodies to effect optical resolution of racemic mixture of amino acid derivatives and to prepare optically active amino acids. Because the present invention allows very easy production of optically active amino acids having various substituted groups, it can contribute to basic studies on the function of living bodies, development of a novel medical drug containing optically active amino acids as an essential component, and development of methodologies for synthesizing various optically and physiologically active substances or functional compounds, which methodologies use optically active amino acids in synthesizing processes.
2. Description of the Related Art
Proteins, a primary component of the living body, are constructed with optically active amino acids, which makes a chiral environment in the living body. Therefore, many of the physiologically active substances including medical drugs are optically active substances, and it is known that bioactivity is found only in either one of enantiomers, or difference in bioactivity is observed between the enantiomers. Accordingly, developing a methodology for obtaining optically active substances is one of the targets of investigations.
The simplest process usually performed to obtain an optically active amino acid derivatives is optical resolution of racemic mixture of amino acid derivatives. The process for optical resolution includes a process employing an enzyme (e.g. a kinetic optical resolution using aminoacylase, lipase and the like) and a process forming a diastereomer, or the like. However, most suitable process must be selected depending on a particular amino acid to be resolved, because there is no common process effective for all the amino acids having a variety of substituted groups.
In such a situation as mentioned above, the inventors of the present invention have succeeded in developing a process for performing optical resolution of racemic mixture of amino acid derivatives, using catalytic antibodies, which is applicable for any amino acids. Although reactions using catalytic antibodies usually have drawbacks in that the catalytic antibodies have substrate specificity, and therefore, they have only limited applicablity, the present inventors have overcome such drawbacks by developing catalytic antibodies which enantioselectively hydrolyze ester derivatives of racemic mixture of any amino acid derivatives to produce corresponding optically active amino acids.